1. Field of the Invention
The instant disclosure relates to a method of transferring a thin film; in particular, to a method of transferring a thin film of an optoelectronic element from a growth substrate to other substrates.
2. Description of Related Art
Thin film solar cells are currently of great potential for energy development projects. The thin film solar cell with a light absorbing layer having a thickness of 2 μm can provide a light energy conversion efficiency of 10 to 20%, so as to effectively decrease material consumption. Since the thin film solar cell has the thin film feature, it can be adapted to flexible substrates and portable equipment. However, the temperature of manufacturing the light absorbing layer of the thin film solar cell is above 600° C., thus the light absorbing layer cannot be deposited on a flexible substrate which has a lower heat resistance, which limits applications of the thin film solar cell.
In the prior art, a manufacturing process at a relatively low temperature has been developed to form the thin film solar cell on different flexible substrates. But, in the current manufacturing process of forming a CIGS light-absorbing layer, reducing the temperature of the substrate is limited. In addition, CIGS light-absorbing layer being manufactured at the relatively low temperature has inferior quality and light energy conversion efficiency. Therefore, the CIGS light-absorbing layer manufactured at the relatively low temperature needs to conduct a selenide annealing treatment (annealing temperature is at least 550° C.), so as to have a superior light energy conversion efficiency.